This invention relates to sealing devices formed from laminated constructions and, more specifically, to sealing devices, e.g., seal rings and methods for forming the same, that are formed from polymer laminated metallic sheet constructions.
Sealing devices, such as seal rings or the like, are well known in the art for providing a seal between opposed sealing surfaces. Such sealing devices can be used to provide a leak-tight seal between sealing surfaces that are static with respect to one another, and/or between sealing surfaces that are dynamic relative to one another, e.g., between a static and dynamic, or between two dynamic sealing surfaces. An example type of dynamic sealing application is a seal ring that is disposed between a static housing and a dynamic rotary or reciprocating sealing surfaces.
Such seal devices can be configured differently, depending on the specific sealing application. For example, seal rings can be configured in the form of a lip seal, comprising one or more lip elements that are designed to project away from the seal body to make contact with the dynamic sealing surface, or in the form of an energized seal, comprising one or more seal elements that are pressed into contact with a dynamic sealing surface by an energizing member disposed within the seal ring. Such seal rings can be used for oil or non-oil sealing applications, or for any type of gas or fluid sealing application.
Lip seals are well known in the art, and can be constructed to include a non-flexible metallic seal member and a relatively conformable nonmetallic, e.g., polymeric, seal member. The metallic seal member is typically in the form of a casing that is configured both to fit within a predetermined seal gland, and to provide a mounting substrate for the nonmetallic seal member. More specifically, the metallic seal member is in the form of a ring-shaped casing that is designed to provide a predetermined amount of compression or tension to the attached nonmetallic seal member forming the lip. In some cases, the ring-shaped casing can be formed from a number of different non-flexible metallic seal elements that are attached together in a predetermined arrangement to both retain and provide the desired tension or compression load onto the nonmetallic seal lip member.
Energized seals are well known in the art, and can be constructed to include a seal body formed from either a metallic or nonmetallic material, depending on the particular seal application, and an energizing member positioned within the seal body to urge a portion the seal body into contact with the dynamic sealing surface. In one application example, the energized seal comprises an annular-shaped seal body that is formed from a relatively flexible or conformable polymeric material, and an energizer formed from a metallic material that is disposed within a channel defining the U-shaped the seal body. Depending on the specific sealing application, such U-shaped seals can be used to provide a radial sealing surface, e.g., between a radially aligned dynamic sealing surface and an inside or outside diameter surface of the seal body, or to provide an axial seal surface, e.g., between an axially aligned dynamic sealing surface and an inside or outside diameter surface of the seal body.
Such known lip seals and energized seals are formed according to a multi-step process that involves both forming the different seal members, e.g., the metallic seal member and/or the polymeric seal member, and attaching the different seal members together. For example, lip seals know in the art are constructed by first forming the metallic casing, be it a single metallic element or multiple metallic elements, by machining and/or molding process, and then separately forming the polymeric lip member by machining and/or molding process. Once the separate metallic and polymeric seal members are formed, they are attached together by conventional chemical and/or mechanical attachment techniques. This construction process of having to separately form the seal members and attach the same is both time consuming and labor intensive, affecting both the production rate and cost of making the same.
There is, therefore, a need for a seal device having a simplified construction that enables/facilitates fabrication in a manner that avoids one or more manufacturing steps, thereby both increasing the production rate and reducing the labor and/or material costs associated with making the same. It is also desired that such seal devices be capable of providing such manufacturing efficiencies without compromising sealing performance when compared to conventional seals. It is still further desired that such seal devices be capable of retrofit use within existing seal housings, thereby replacing conventional seal devices without any or only minimal seal housing modification.
Seal devices are prepared according to principles of this invention by shape molding a preformed composite construction comprising a polymer laminated metallic substrate. The seal device may be configured differently depending on the particular seal application, however, generally comprises a rigid casing member (formed by the metallic substrate portion of the construction), and a relatively compliant sealing element attached thereto (formed by the polymeric material). Alternatively, seal devices of this invention can be configured from the composite construction such that the metallic substrate is in the form of a resilient member to provide a desired loading force onto the compliant sealing element.
Seal devices constructed from such laminated or composite constructions provide a manufacturing advantage in making seal rings, when compared to seal devices made according to conventional practice, in that use of such preformed laminated construction avoids the need to: (1) separately make and form individual sealing members (i.e., make and form a separate casing member and sealing element); and (2) subsequently join or assemble the separately created sealing members together. Rather, seal devices can be made according to this invention by a simple process of form shaping both sealing members at once, thereby resulting in labor cost savings, material cost savings, and increased manufacturing production rates.